1. Field of the Invention
The present invention relates to an apparatus for refilling cylinders. More particularly, the invention concerns an apparatus for refilling high-pressure fluid storage vessels or cylinders of the type used with paintball guns or markers.
2. Reference to Related Art
In the sport of paintball, players can take on the role of enemy combatants. To defeat the opposition, each player uses a pneumatically actuated paintball marker or gun to shoot or otherwise project paint-filled spheres known as paintballs at one another. When a player is struck by a paintball, the paintball shatters splattering the affected player with an amount of paint. Striking a player in this manner can result in the elimination of that player from a game.
Modern paintball guns or markers generally include three elements: 1) the gun; 2) a magazine attached to the gun that holds a supply of paintballs that are fed into the gun; and 3) a pressure supply that is usually maintained at a pressure of 3000-4500 psi and may comprise a fluid cylinder or tank filled with a fluid such as nitrogen, compressed air or high-pressure air (HPA). The pressure supply is attached to the gun and is adapted to provide the gun with the necessary pneumatic power to project a paintball toward one""s opponent.
Given the high-pressures used to power a modem paintball marker, it would be advantageous to have a safe and convenient system for refilling a fluid cylinder once that cylinder is exhausted. In recent years, it has been commonplace to have a team of two people involved in a cylinder refilling process, with one person holding a fluid cylinder and/or a quick disconnect fitting and another person controlling the flow of a pressured fluid from a high-pressure supply source to the fluid cylinder. However, the possibility of a fill line or cylinder rupture during the refill process makes this modem two-person practice unsafe since such a rupture might easily result in an injury to all persons involved in the refill process. Therefore, it would be advantageous to have a self-serve cylinder refill apparatus that removes one person from the process of refilling the cylinder and also make the refilling process safe and practical.
The present invention provides a cylinder refilling apparatus that includes a housing, a high-pressure and a low-pressure fluid source. The housing has a cylinder refill circuit that includes a high-pressure circuit adapted to refill a cylinder and a low-pressure circuit that operates to open and close the high-pressure circuit. More particularly, the high-pressure circuit includes an inlet in communication with the high-pressure fluid source, a normally closed valve in communication with the inlet, a normally open valve in communication with the normally closed valve and an outlet in communication with the normally closed valve.
The low-pressure circuit communicates with (and when charged actuates) the normally open valve and normally closed valve and also includes: an inlet in communication with the low-pressure fluid source; a fill valve; and a muffler in communication with the fill valve. The fill valve is movable between a first and a second position such that moving the fill valve into the second position operates to charge the low-pressure circuit which then actuates the normally closed valve and the normally open valve. Additionally, the high and low-pressure circuits are adapted to safely vent into the atmosphere any pressurized fluid that may be resident in either circuit following the termination of a cylinder refilling operation.
During a refilling operation, a user first connects a fluid cylinder to the high-pressure outlet of the apparatus. The user next takes a position in front of the apparatus, away from the higher pressure source, and depresses the fill valve. When the user depresses the fill valve, low-pressure fluid is supplied to both a normally closed valve and a normally open valve in the high-pressure circuit. This action will allow high-pressure fluid to flow from the normally closed valve to a check valve. From the check valve the fluid flows to a pressure gauge and the normally open valve (which is closed due to the fill valve being depressed). From the gauge the high-pressure fluid flows through an outlet hose and into the fluid cylinder attached to the hose.
When the gauge indicates a predetermined pressure or the user hears the flow of fluid stop, the user releases the fill valve. When the user releases the fill valve, the fluid in the low-pressure circuit that is supplied to the normally closed valve and the normally open valve is vented through a muffler and into the atmosphere. Venting of the low-pressure fluid in this manner causes the normally closed valve to close and the normally open valve to open. This action will cause high-pressure fluid to stop flowing to the outlet hose and will allow pressure in the high-pressure circuit to be vented through the normally open valve and a muffler. At this time the filling process is complete and the user can disconnect the cylinder from the hose without the fear of the hose being pressurized.
The present invention for a self-serve cylinder refill apparatus provides a safe and practical means of refilling high-pressure cylinders that may be attached to paintball markers. The invention has several advantages. For example, the present invention allows a single user to conduct a fluid cylinder refill operation while positioned a safe distance from either the high-pressure fluid source or the fluid cylinder. This ability to allow remote refilling of fluid cylinders increases safety and decreases the possibility of injury in the event of a rupture.